1. Field of the Invention
The present invention relates to an adaptive image processing method and related device, and more particularly, to an adaptive image processing method capable of detecting and compensating defect pixels and a related device.
2. Description of the Prior Art
Image sensing elements such as CMOS image sensors (CIS) and charge-coupled devices (CCD) have been widely applied in various consumer electronic products such as digital cameras, personal digital assistants (PDAs) and smart mobile communication devices. Part of the image sensing pixel units of the image sensing element may work abnormally due to process variations, meaning the pixel values corresponding to the abnormal image sensing pixel units will be erroneous. The abnormal image sensing pixel unit is called a defect pixel. Defect pixels may also randomly exist in the image due to environmental factors present when capturing the image, such as temperature, brightness, and photosensitivity.
After the image sensing element captures the image, the image sensing element must use an image processing device for compensating the pixel values of the defect pixels, so that the pixel values of the defect pixels will not decrease the image quality when image enhancement procedures such as image sharpness are performed. In the prior art, the image processing device can acquire positions of the defect pixels through defect pixel information and then compensate the defect pixels by calculating average pixel values of adjacent pixels for each defect pixel. The defect pixel information is acquired by testing when the consumer electronic product is manufactured, and is stored in the memory of the consumer electronic product. As a result, the image processing device has to read the defect pixel information from the memory each time the image sensing element captures the image, to compensate each defect pixel.
Since the defect pixel information is acquired when the consumer electronic products is manufactured, the defect pixels recorded in the defect pixel information do not include the above-mentioned random defect pixels, and these random defect pixels therefore cannot be compensated. In addition, the defect pixel information needs to be stored in the memory. If the image processing device can adaptively and accurately detect the defect pixels, all the defect pixels in the image can be compensated and the memory utilized for storing the defect pixel information will no longer be needed.